I've never had the opportunity to visit this gallery but I definitely want to go on my next Big Bend trip. What I find so interesting about this place is how there is a beautiful and strange bubble of mordern art out in the middle of nowhere. This place is otherworldly. If you go, just enjoy the experience and take some artsy photos. ;)
If you are looking for something exciting to do, this is another site full of information regarding hiking, river trips, horseback riding, air tours, and MORE. There really is a lot to do in the Big Bend area so if I have missed something in my list of recommendations, you will probably find it on this site.